Kristen Stewart Channels Joan Jett

It's only been a couple of weeks since shooting wrapped on New Moon, but Kristen Stewart has already undergone a dramatic transformation in preparation for her next role. The actress has been spotted at rehearsals for her new flick The Runaways—the story of the iconic '70s all-girl rock band—with much shorter and darker-colored locks.

She's been keeping the new 'do under wraps in either in a pony tail or tucked under a hoodie, but since she's playing Joan Jett in the flick, it's safe to say we'll be seeing her out-and-about soon with the music icon's signature shag.